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Mathematical model of dynamic imbibition in nanoporous reservoirs

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Petroleum Exploration and Development 2022年第1期49卷 170-178页

作者： TIAN Weibing wu Keliu CHEN Zhangxing LEI Zhengdong GAO yanling li Jing China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China Department of Chemical and Petroleum Engineering University of CalgaryAlberta T2N 1N4Canada PetroChina Research Institute of Petroleum Exploration&Development Beijing 100083China

The oil-water imbibition equation in the nano-scale pores considering the dynamic contact angle effect, nanoconfinement effect, inertia effect, and inlet end effect was established, and the relation between the friction coefficient of solid-oil-water three-phase contact line and the fluid viscosity in the interface zone was derived. In combination with the capillary bundle model and the lognormal distribution theory, the imbibition model of tight core was obtained and key parameters affecting imbibition dynamics were analyzed. The study shows that in the process of nanopore imbibition, the dynamic contact angle effect has the most significant impact on the imbibition, followed by nanoconfinement effect(multilayer sticking effect and slippage effect), and the inertia effect and inlet end effect have the least impact;in the initial stage of imbibition, the effect of inertial force decreases, and the effect of contact line friction increases, so the dynamic contact angle gradually increases from the initial equilibrium contact angle to the maximum and then remains basically stable;in the later stage of imbibition,the effect of contact line friction decreases, and the contact angle gradually decreases from the maximum dynamic contact angle and approaches the initial equilibrium contact angle;as the pore radius decreases, the dynamic contact angle effect increases in the initial stage of imbibition and decreases in the later stage of imbibition;as the oil-water interfacial tension increases, the imbibition power increases, and the dynamic contact angle effect increases;there is a critical value for the influence of interfacial tension on the imbibition dynamics. In improving oil recovery by imbibition in tight oil reservoir, interfacial tension too low cannot achieve good imbibition effect, and the best interfacial tension needs to be obtained through optimization.

关键词： tight reservoir nanopore capillary imbibition model imbibition dynamics influencing factors

温针灸结合电脑中频刺激对腰椎间盘突出症的治疗效果

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中国伤残医学 2024年第9期32卷 60-63页

作者：李建华天津市武清区河西务医院中医科天津301714

目的:探讨温针灸结合电脑中频刺激对腰椎间盘突出症(LDH)患者的治疗效果。方法:选择2021年1月-2023年1月本院收治的160例腰椎间盘突出症患者作为研究对象,根据1:1分配原则将患者分为联合组与对照组,各80例,对照组采用温针灸治疗,联合组... 详细信息

目的:探讨温针灸结合电脑中频刺激对腰椎间盘突出症(LDH)患者的治疗效果。方法:选择2021年1月-2023年1月本院收治的160例腰椎间盘突出症患者作为研究对象,根据1:1分配原则将患者分为联合组与对照组,各80例,对照组采用温针灸治疗,联合组在对照组基础上采用电脑中频刺激,2组均治疗观察4周,对比2组患者的治疗效果。结果:治疗第1、2、4周,联合组VAS评分均低于对照组,组间差异有统计学意义(P<0.05)。联合组并发症发生率低于对照组,差异有统计学意义(P<0.05)。治疗后,2组血清IL-6、TNF-α、CRP含量均低于治疗前,且联合组低于对照组,差异有统计学意义(P<0.05)。结论:温针灸结合电脑中频刺激用于腰椎间盘突出症患者能减少并发症,改善炎症,缓解患者疼痛。

关键词：腰椎间盘突出症温针灸电脑中频刺激并发症炎症因子疼痛

Tracking Catalytic Esterification of Naphthenic Acids in Crude Oil by ESI FT-ICR MS

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China Petroleum Processing & Petrochemical Technology 2016年第3期18卷 57-65页

作者： li Xiaohui wu Bencheng Zhu jianhua Tao Xiujuan College of Chemistry and Chemical Engineering Xi'an Shiyou University College of Chemical Engineering China University of PetroleumBeijing Key Laboratory of Auxiliary Chemistry and Technology for Chemical Industry Shaanxi University of Science and Technology

The catalytic esterification reaction was used to decrease total acid number(TAN) of crude oil by converting naphthenic acids to naphthenic acid esters in the presence of Zn-Al hydrotalcite used as the catalyst and glycol used as the reactant. The crude oil and its corresponding esterified oil were characterized by the negative-ion electrospray ionization(ESI) Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS). Six acidic class species, O_2, O_1, N_1, N_2, N_1O_1 and N_1O_2 were assigned in the negative-ion spectrum both in the crude oil and its esterified oil. Among the identified acidic compounds, the O2 class was dominant. The relative abundance of O_2 class species was much higher than other acidic class species in crude oil, while it was significantly decreased after esterification. The most abundant O_2 class species had a carbon number of 30-34 and a double-bond equivalence(DBE) value of 5 before and after esterification. It could be concluded that the naphthenic acids in crude oil can be esterified to lower its TAN value, and each of them seems to exhibit identical esterification efficiency approximately due to the similar DBE versus the-carbon number distribution before and after esterification.

关键词： naphthenic acids crude oil esterification ESI FT-ICR MS

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木质素生物降解的脱甲基机制研究进展

微生物学通报 2024年第6期51卷 1834-1853页

作者：吴艳玲薛乐卢鹏李安东廖庆钊陈先锐肖宁谢尚县广西科学院非粮生物质能技术全国重点实验室广西南宁530007 华中科技大学生命科学与技术学院湖北武汉430074

木质素是由苯丙烷结构单元通过多种化学键交联组成的复杂芳香族高聚物。由于其结构的复杂性和异质性,使得木质素的高效降解与经济转化成为了一个世界性的难题。近年来,科学研究发现微生物特有的非特异性氧化还原体系及芳香族化合物多元... 详细信息

木质素是由苯丙烷结构单元通过多种化学键交联组成的复杂芳香族高聚物。由于其结构的复杂性和异质性,使得木质素的高效降解与经济转化成为了一个世界性的难题。近年来,科学研究发现微生物特有的非特异性氧化还原体系及芳香族化合物多元代谢降解能力,为解决木质素的资源化利用提供了新的思路和方向。由于大部分木质素衍生的芳香族单体在苯环不同位置上都含有甲氧基,使得脱甲基化成为了木质素衍生芳香族化合物代谢的关键限速步骤。本综述就近年来在木质素生物降解过程中的脱甲基生物学和酶学机制研究进行了较为全面的总结,并以利用芳香族脱甲基酶进行木质素高值转化方面的典型研究案例进行分析,阐明了微生物脱甲基过程机制解析以及新型脱甲基酶的挖掘对于木质素降解与转化的重要意义。

关键词：脱甲基酶木质素生物降解代谢工程生物质

High Sensitive Ambipolar Response towards Oxidizing NO2 and Reducing NH3 Based on Bis（phthalocyaninato） Europium Semiconductors

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Chinese Journal of Chemistry 2016年第10期34卷 975-982页

作者： Xia Kong Zhen Dong yanling wu Xiyou li Yanli Chen Jianzhuang Jiang School of Science China University of Petroleum (East China) Qingdao Shandong 266580 China Beymg Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials Department of Chemistry University of Science and Technology Beijing Beijing 100083 China

High sensitive chemical sensors towards NO2 and NH3 based on the self-assembled nanostructures of the heteroleptic and homoleptic bis（phthalocyaninato） europium complexes with octanaphthoxy phthalocyaninato ligands named Eu（Pc）[Pc（ONh）8] （1） and Eu[Pc（ONh）8]2 （2） [Pc = unsubstituted phthalocyaninate; Pc（ONh）8 = 2,3,9,10,16,17,23,24-octanaphthoxy phthalocyaninate] have been developed. The good conductivity, high crystal- linity and large specific surface area for the self-assemblies of 1 render it excellent sensing property for either electron-accepting gas NO2 in 50--250 ppb range or electron-donating gas NH3 in 2.5--12.5 ppm range due to the optimized molecular packing in the uniform-sized nanopartieles depending on the effective intermolecular interaction between double-decker molecules, among the best results of phthalocyanine-based chemical sensors for detection of NO2 and NH3 at room temperature. Interestingly, self-assemblies of I exhibited n-type response to NO2 and p-type response to NH3, which is the first example of ambipolar charge-transporting gas sensors fabricated from single- component organic semiconductors. However, the self-assemblies of 2 with sixteen bulky naphtboxy groups at the periphery of two Pc rings only present an n-type response to strong oxidant gas NO2 in a relatively high concentration of 0.5 - 1.5 ppm, while are insensitive to weak reducing gas NH3 due to the existence of great steric hindrance from bulky naphthoxy groups and more traps and/or defects in self-assemblies.

关键词： phthalocyanine double-decker gas sensor self-assemblies ambipolar semiconductor

Effect of sodium tartrate concentrations on morphology and characteristics of anodic oxide film on titanium alloy Ti–10V–2Fe–3Al

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Chinese Journal of Aeronautics 2016年第4期29卷 1151-1158页

作者： Ma Kun Yu Mei liu jianhua li Songmei wu liang Yao Wenhui School of Materials Science and Engineering Beihang University School of Materials Science and Engineering Chongqing University

The effect of sodium tartrate concentrations on morphology and characteristics of anodic oxide film on titanium alloy was investigated. The alloy substrates were anodized in different concentration solutions of sodium tartrate with the addition of PTFE emulsion and their morphology and characteristics were analyzed. The anodic oxide film presented a uniform petaloid drums and micro-cracks morphology. Additionally, micro-cracks dramatically swelled with the increase of the tartrate concentrations. The thickness of the anodic oxide film increased with the concentrations until the concentration reached 15 g/L. The results of Raman analysis illustrate that all samples have similarity in the crystal structure, consisting of mainly amorphous TiO2, some anatase TiO2and a small amount of rutile TiO2. And the ratios of anatase TiO2and rutile TiO2increase with the concentrations until it reaches 15 g/L. Furthermore, the intensity of the peaks increases with enhanced concentrations until the concentration reaches 15 g/L. The corrosion resistance of the anodic oxide film is increased by the sodium tartrate with higher concentrations before 15 g/L. The coefficient of friction of the anodic oxide film reduces with the concentrations until the concentration reaches 15 g/L, then the coefficient of friction of the anodic oxide film increases with the concentrations. © 2015 The Authors

关键词： Concentration (process) Corrosion Corrosion inhibitors Corrosion resistance Cracks Crystal structure Emulsification Friction Morphology Oxide films Oxide minerals Sodium Titanium Titanium alloys Titanium dioxide Titanium oxides Tribology

Formation of the Moping Dome in the Xuefengshan Orocline, Central China and its Tectonic Significance

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Acta Geologica Sinica(English Edition) 2013年第3期87卷 720-729页

作者： SHI Wei DONG Shuwen li jianhua TIAN Mi wu Guoli Institute of Geomechanics Chinese Academy of Geological Sciences Key Laboratory of Neotectonic Movement and Geohazard Ministry of Land and Resources Chinese Academy of Geological Sciences wuxi Research Institute of Petroleum Geology SINOPEC Institute of Geology and Geophysics Chinese Academy of Sciences

Many equiaxial dome-like structures developed in the north segment of the Xuefengshan orocline, Central China are obviously inconcordant with the NE-trending linear structures in this area, which contain important records for understanding the structural framework and evolution of this belt. In this paper, taking one of the typical dome-like structures in the Xuefengshan orcline （e.g. Moping dome-like structure） as an example, based on its structural framework interpratatoin, superposed deformation analysis and paleo-stress fields reconstruction, we propose the Moping dome- like structure is composed of two populations of different-striking thrust-fold structures, -E-trending and NE-striking structures, indicative of two-stages shortening, -N- and NW-striking, respectively. Together with the geochronological analysis, we suggest the first stage of shortening occurred in Late Triassic to Early Jurassic, due to the Indosinian intercollisional orogeny of the Yangtze Block and the North China Block. The second occurred during Late Jurassic-Early Cretaceous owing to Yanshanian intracontinental orogeny, leading to the intensive superposition of the NE-trending structures onto the -E-trending structures, and the final ocurrence of the Moping dome. Thus, our study indicates the Xuefengshan arc-shape belt also experienced two-phase deformation, and resulted from the superposition of NE-SW structures onto -E-W structures in Late Jurassic-Early Cretaceous, which could provide new structural evidence for probing the Mesozoic tectonic framework and evolution of the Xuefengshan orocline.

关键词： Xuefengshan orocline Moping dome superposed structure paleo-stress field intracontinental orogeny

Precise absolute positioning for a single-frequency user

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Science China(Physics,Mechanics & Astronomy) 2013年第8期56卷 1591-1597页

作者： li HaoJun TANG GuiFeng HE Feng wu Bin HU XiaoGong CHEN yanling Shanghai Astronomical Observatory Chinese Academy of Sciences Guangxi Key Laboratory of Spatial Information and Geomatics Guilin University of Technology Shanghai Key Laboratory of Space Navigation and Position Techniques Beijing Satellite Navigation Center

A new strategy to realize precise absolute positioning for a single-frequency user is presented. In the presented strategy, the receiver clock and ambiguities are removed using the satelliteand epoch-differenced (SDED) algorithm. As a further development of the SDED algorithm, a regional augmentation network is used to generate the SDED atmospheric delays at the user. The weakened mathematic property due to the epoch-differenced operation is improved by adding the generated atmospheric delays and applying the robust estimation. To test the new approach, the 24-h data at 5 Continuous Operation Reference Station (CORS) stations in Shanghai is processed. The results show a more than 96% success rate, defined as the case where three directions achieve the desired positioning accuracy of 10 cm, when the observation is longer than 20 min. The 20-min static results show that the new method can reach an accuracy of 3.42, 4.76 and 9.26 cm in the North, East and Up directions, respectively. An experiment was carried out to assess the kinematic positioning. The results show that the kinematic positioning accuracy is 4.11, 5.31 and 4.05 cm in the north-south, east-west and height directions,respectively.

关键词： absolute positioning single-frequency user correction information

Event-Oriented Dynamic Security Service for Demand Response in Smart Grid Employing Mobile Networks

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China Communications 2015年第12期12卷 63-75页

作者： GUO Longhua DONG Mianxiong Kaoru Ota wu Jun li jianhua School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University Department of Information and ElectronicEngineering Muroran Institute of Technology

Equipped with millions of sensors and smart meters in smart gird,a reliable and resilient wireless communication technology is badly *** networks are among the major energy communication networks which contribute to global energy consumption increase *** one of core technologies of smart grid employing mobile networks,Demand Response(DR) helps improving efficiency,reliability and security for electric power grid *** of DR events is one of the most important issues in ***,the security requirements of different DR events are dynamic for variousactual *** address this,an event-oriented dynamic security service mechanism is proposed for *** kinds of security services including security access service,security communication service and security analysis service for DR event are composited dynamically by the fine-grained sub *** experiment prototype of the network of State Grid Corporation of China(SGCC) is *** and evaluations shows the feasibility and effectiveness of the proposed scheme in smart grid employing mobile network.

关键词： dynamically smart overhead infrastructure broadcast badly password electricity prototype authentication